How to Buy a Good Sleeping Bag

A sleeping bag can make the difference between blissful comfort and a verrry long, miserable night. It can even help you ward off life-threatening hypothermia if you get cold and wet.

Follow these tips on choosing the right sleeping bag for your next adventure and check out the Gear Guy’s favorite models.

KNOW THYSELF

If you are warm-natured, get a bag rated about 10 degrees lower than the lowest temperatures you typically encounter on trips. If you are cold-natured, get a bag rated 20 to 25 degrees lower than the coldest nights you anticipate.

BSA 30° F Mummy Sleeping Bag – Youth ($59.99, scoutshop.org): Warm enough for most autumn nights, this 6-foot-long bag is big enough for a Scout to grow into and has everything you need in a basic sleeping bag. The durable 70-denier nylon ripstop shell is what you’ll find in many models costing two or three times as much, making it a great value. 2 lbs., 13 oz.; rated to 30° F

KNOW YOUR BUDGET

Sleeping bag prices can vary from $60 to $600, depending on factors such as:

INSULATION

There are two main types of insulation: down, which is natural, and synthetic, which is man-made. Generally, goose down is warmer, lighter and easier to pack, but it’s typically more expensive and requires extra care. The biggest downside to down is that it loses its ability to keep you warm if it becomes wet.

Synthetic insulation, like PrimaLoft, is typically less expensive, requires little care and retains its warmth if the bag gets wet. Synthetic sleeping bags are heavier than down competitors, but they remain the best choice for routinely wet adventures.

To blur the line, you can now buy water-resistant down, which retains its ability to trap heat when wet. Still, even saturated water-resistant down loses some of its ability to trap heat, and you might have trouble drying out any bag in prolonged wet weather.

Kelty Dualist 20 (Starting at $139.95, kelty.com): This hybrid-insulation mummy delivers big value for its small price. It combines 550-fill water resistant down as an outer layer of insulation with synthetic insulation next to your body. This helps keep the bag lightweight while still trapping heat when wet. It is, however, heavier and bulkier than more expensive bags. Available in two lengths. 3 lbs., 3 oz.; rated 33° F (comfort) to 22° F (limit)

WEIGHT

This matters when you’re backpacking, but not so much when you’re car camping. Lighter, higher-quality insulation costs more, but you can trim weight and bulk simply by buying the right bag for the conditions.

Western Mountaineering Summerlite (Starting at $390, westernmountaineering.com): Ultralight bags often come with tradeoffs: thin insulation and a cramped fit or lacking features like a full-length zipper or hood. Not the Summerlite, which comes in three lengths. Packed with 850-fill down feathers, it was toasty on late-March nights below freezing in southern Utah. Continuous baffles let you move feathers to the top or bottom. Really cool: the bag packs into a 1-ounce stuff sack that’s slightly larger than a loaf of bread. 1 lb., 3 oz.; rated to 32° F

TEMPERATURE RATINGS

You’ll notice labels with ratings like -10 degrees or +30 degrees, which tell you the lowest temperature at which most people will be comfortable sleeping in that particular bag. Price is affected by both the quality and amount of insulation, so price goes up as rating goes down.

Feathered Friends Snowbunting EX 0 ($599, featheredfriends.com): For winter camping or climbing a big mountain, the Snowbunting EX 0 excels. With 25 generous ounces of sustainably produced, 900-plus-fill down, it was a cocoon for the Gear Guy on frigid nights during an April ascent of California’s Mount Whitney. Bonus: Its bulk and weight compare with many three-season (roughly 20° F) bags. 2 lbs., 12 oz.; rated to 0° F

SHAPE

Mummy bags taper from head to foot for thermal efficiency and to minimize weight and bulk, but some can feel claustrophobic. Rectangular bags are more spacious but are generally heavier and bulkier, and you can sometimes hit a cold spot. Try it on before buying.

Big Agnes Haybro 15 ($99.95, bigagnes.com): Sized for teens up to 5 feet 6 inches, the mummy-style Haybro is more spacious than many mummies but designed for thermal efficiency with the Big Agnes sleep system: Slide any 20-inch-wide air mattress (purchased separately) into a sleeve on the bag’s bottom side, and there’s no need for insulation on the bag’s bottom. 2 lbs., 14 oz.; rated to 15° F

CONSTRUCTION

Less expensive — yet lightweight — bags have sewn-through baffles, which can create cold spots along seams. Higher-quality horizontal baffles are typically warmer. Other high-quality construction upgrades include a draft tube (along the zipper), a collar (inside the hood) and a no-snag zipper guard.

Exped DreamWalker Camp 450 (Starting at $219, exped.com): Is it a sleeping bag or a down jacket? With a draw cord at the foot end, a full-length center zipper and zippered arm openings, the DreamWalker (available in three lengths) converts from a bag to a blanket to a parka. Stuffed with 700-fill down, this mummy kept the Gear Guy warm on nights that dropped into the 30s. 1 lb., 14 oz.; rated 39° F (comfort) to 33° F (limit)

GEAR GUY’S ADVICE?

Get what you can afford. You can still get outside with an inexpensive bag — which is what’s most important, right? If and when you have the dough for a nicer bag, your wilderness adventures will be a little more luxurious.

CARING FOR YOUR BAG

Properly cared for, a sleeping bag can last 10 to 20 years. Body oils can compromise insulation, so you should always sleep in clean base layers. Post-trip, hang the bag to dry for a day or two, and then place it in a big storage sack and keep in a dry place. If your bag gets really dirty or starts losing loft, follow manufacturer instructions for washing it.